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Remote C-H Functionalization of 8-Aminoquinoline Ring
Zhihui Xu1, Xiaogang Yang1, Shuang-Feng Yin1
1State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, People's Republic of China.
Topics in Current Chemistry (Cham)
|June 12, 2020
Summary
This review details the synthesis of substituted 8-aminoquinolines, crucial for drug discovery. It covers C-C and C-heteroatom bond formation using various catalysts, often involving single electron transfer (SET) mechanisms.
Area of Science:
- Organic Chemistry
- Medicinal Chemistry
- Catalysis
Background:
- 8-Aminoquinoline is a vital heterocyclic scaffold found in natural products, materials, and pharmaceuticals.
- It serves as a directing group or ligand auxiliary for C-H bond activation and functionalization.
- Synthesizing substituted 8-aminoquinolines is critical for developing new chemical entities.
Purpose of the Study:
- To review recent advances in the functionalization of the 8-aminoquinoline ring system.
- To cover methods for forming C-C and C-heteroatom bonds at positions C2-C7.
- To highlight catalytic systems and mechanistic insights, particularly single electron transfer (SET).
Main Methods:
- Focus on transition metal catalysis, photocatalysis, and metal-free conditions for C-H functionalization.
- Discussion of synthetic strategies for C-C and C-Z bond formation on the 8-aminoquinoline core.
- Analysis of proposed reaction mechanisms, emphasizing SET pathways.
Main Results:
- Comprehensive overview of functionalization strategies at various positions (C2-C7) of the 8-aminoquinoline core.
- Demonstration of diverse bond formations, including C-C and C-heteroatom linkages.
- Identification of SET as a prevalent mechanistic pathway in many transformations.
Conclusions:
- Substituted 8-aminoquinolines are readily accessible through diverse modern synthetic methodologies.
- The review provides a valuable resource for chemists seeking to functionalize this important heterocyclic framework.
- Understanding the mechanistic underpinnings, such as SET, aids in the rational design of future synthetic approaches.
Keywords:
8-AminoquinolineRemote C–H functionalizationSingle electron transfer mechanismSite-selectiveMore Related Videos
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